I recently made a dumb (in retrospect) mistake that set me back a lot. Feeling upset and regretful, I spoke to an older family member who reassured me, "yeah, unfortunately there's no way around it; we have to experience these mistakes personally in order to learn from them".

I thought, is that actually true? Can't we learn from other people's mistakes? After all, isn't that the whole point of studying history, or listening to other people's advice, etc? I'm sure that every mistake I could possibly make has been made by countless people before me and discussed in depth somewhere.

This thought inspired me to try to see what I can learn about mistakes by reading about other people's experiences.

I first tried looking at history for examples of famous instances of dumb mistakes made by smart people. I used LLMs and some scripting to (1) generate many examples of mistakes from different periods of history, and (2) summarize/extract/categorize them, so that I could browse by cognitive principle. It generated lots of interesting cases, such as:

Ignaz Semmelweis dismisses need to persuade (Vienna, 1840s)
- discovers handwashing saves lives, then refuses to publish [...]

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First published:
June 20th, 2026

Source:
https://www.lesswrong.com/posts/J8L3HoPYAj52x9gCA/would-anybody-here-be-interested-in-a-mistake-postmortem

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Narrated by TYPE III AUDIO.

“Would anybody here be interested in a “mistake postmortem” discussion group?” by SK2

LessWrong (30+ Karma)

“Would anybody here be interested in a “mistake postmortem” discussion group?” by SK2